path: root/src/common/xmpp/client_nb.py

##   client_nb.py
##	   based on client.py, changes backported up to revision 1.60
##
##   Copyright (C) 2003-2005 Alexey "Snake" Nezhdanov
##	   modified by Dimitur Kirov <dkirov@gmail.com>
##
##   This program is free software; you can redistribute it and/or modify
##   it under the terms of the GNU General Public License as published by
##   the Free Software Foundation; either version 2, or (at your option)
##   any later version.
##
##   This program is distributed in the hope that it will be useful,
##   but WITHOUT ANY WARRANTY; without even the implied warranty of
##   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
##   GNU General Public License for more details.

# $Id: client.py,v 1.52 2006/01/02 19:40:55 normanr Exp $

'''
Client class establishs connection to XMPP Server and handles authentication
'''
import socket
import transports_nb, dispatcher_nb, auth_nb, roster_nb, protocol, bosh
from protocol import NS_TLS

import logging
log = logging.getLogger('gajim.c.x.client_nb')


class NonBlockingClient:
	'''
	Client class is XMPP connection mountpoint. Objects for authentication,
	network communication, roster, xml parsing ... are plugged to client object.
	Client implements the abstract behavior - mostly negotioation and callbacks
	handling, whereas underlying modules take care of feature-specific logic.
	'''
	def __init__(self, domain, idlequeue, caller=None):
		'''
		Caches connection data:

		:param domain: domain - for to: attribute (from account info)
		:param idlequeue: processing idlequeue
		:param caller: calling object - it has to implement methods 
			_event_dispatcher which is called from dispatcher instance
		'''
		self.Namespace = protocol.NS_CLIENT
		self.defaultNamespace = self.Namespace

		self.idlequeue = idlequeue
		self.disconnect_handlers = []

		self.Server = domain
		self.xmpp_hostname = None # FQDN hostname to connect to

		# caller is who initiated this client, it is in needed to register
		# the EventDispatcher
		self._caller = caller
		self._owner = self
		self._registered_name = None # our full jid, set after successful auth
		self.connected = ''
		self.socket = None
		self.on_connect = None
		self.on_proxy_failure = None
		self.on_connect_failure = None
		self.proxy = None
		self.got_features = False
		self.stream_started = False
		self.disconnecting = False
		self.protocol_type = 'XMPP'

	def disconnect(self, message=''):
		'''
		Called on disconnection - disconnect callback is picked based on state
		of the client.
		'''
		# to avoid recursive calls
		if self.disconnecting: return

		log.info('Disconnecting NBClient: %s' % message)

		if 'NonBlockingRoster' in self.__dict__:
			self.NonBlockingRoster.PlugOut()
		if 'NonBlockingBind' in self.__dict__:
			self.NonBlockingBind.PlugOut()
		if 'NonBlockingNonSASL' in self.__dict__:
			self.NonBlockingNonSASL.PlugOut()
		if 'SASL' in self.__dict__:
			self.SASL.PlugOut()
		if 'NonBlockingTCP' in self.__dict__:
			self.NonBlockingTCP.PlugOut()
		if 'NonBlockingHTTP' in self.__dict__:
			self.NonBlockingHTTP.PlugOut()
		if 'NonBlockingBOSH' in self.__dict__:
			self.NonBlockingBOSH.PlugOut()
		# FIXME: we never unplug dispatcher, only on next connect
		# See _xmpp_connect_machine and SASLHandler

		connected = self.connected
		stream_started = self.stream_started

		self.connected = ''
		self.stream_started = False
 
		self.disconnecting = True

		log.debug('Client disconnected..')
		if connected == '':
			# if we're disconnecting before connection to XMPP sever is opened,
			# we don't call disconnect handlers but on_connect_failure callback
			if self.proxy:
				# with proxy, we have different failure callback
				log.debug('calling on_proxy_failure cb')
				self.on_proxy_failure(reason=message)
			else:
				log.debug('ccalling on_connect_failure cb')
				self.on_connect_failure()
		else:
			# we are connected to XMPP server
			if not stream_started:
				# if error occur before XML stream was opened, e.g. no response on 
				# init request, we call the on_connect_failure callback because
				# proper connection is not established yet and it's not a proxy
				# issue
				log.debug('calling on_connect_failure cb')
				self._caller.streamError = message
				self.on_connect_failure()
			else:
				# with open connection, we are calling the disconnect handlers
				for i in reversed(self.disconnect_handlers):
					log.debug('Calling disconnect handler %s' % i)
					i()
		self.disconnecting = False

	def connect(self, on_connect, on_connect_failure, hostname=None, port=5222,
	on_proxy_failure=None, proxy=None, secure_tuple=('plain', None, None)):
		''' 
		Open XMPP connection (open XML streams in both directions).

		:param on_connect: called after stream is successfully opened
		:param on_connect_failure: called when error occures during connection
		:param hostname: hostname of XMPP server from SRV request  
		:param port: port number of XMPP server
		:param on_proxy_failure: called if error occurres during TCP connection to
			proxy server or during proxy connecting process
		:param proxy: dictionary with proxy data. It should contain at least
			values for keys 'host' and 'port' - connection details for proxy serve
			and optionally keys 'user' and 'pass' as proxy credentials
		:param secure_tuple: tuple of (desired connection type, cacerts, mycerts)
			connection type can be 'ssl' - TLS established after TCP connection,
			'tls' - TLS established after negotiation with starttls, or 'plain'.
			cacerts, mycerts - see tls_nb.NonBlockingTLS constructor for more
			details
		'''
		self.on_connect = on_connect
		self.on_connect_failure=on_connect_failure
		self.on_proxy_failure = on_proxy_failure
		self.desired_security, self.cacerts, self.mycerts = secure_tuple
		self.Connection = None
		self.Port = port
		self.proxy = proxy

		if hostname:
			self.xmpp_hostname = hostname
		else:
			self.xmpp_hostname = self.Server
		
		# We only check for SSL here as for TLS we will first have to start a 
		# PLAIN connection and negotiate TLS afterwards.
		# establish_tls will instruct transport to start secure connection 
		# directly
		establish_tls = self.desired_security == 'ssl'
		certs = (self.cacerts, self.mycerts)

		proxy_dict = {}
		tcp_host = self.xmpp_hostname
		tcp_port = self.Port

		if proxy:
			# with proxies, client connects to proxy instead of directly to
			# XMPP server ((hostname, port))
			# tcp_host is hostname of machine used for socket connection
			# (DNS request will be done for proxy or BOSH CM hostname)
			tcp_host, tcp_port, proxy_user, proxy_pass = \
				transports_nb.get_proxy_data_from_dict(proxy)
		
			if proxy['type'] == 'bosh':
				# Setup BOSH transport
				self.socket = bosh.NonBlockingBOSH.get_instance(
					on_disconnect=self.disconnect,
					raise_event=self.raise_event,
					idlequeue=self.idlequeue,
					estabilish_tls=establish_tls,
					certs=certs,
					proxy_creds=(proxy_user, proxy_pass),
					xmpp_server=(self.xmpp_hostname, self.Port),
					domain=self.Server,
					bosh_dict=proxy)
				self.protocol_type = 'BOSH'
				self.wait_for_restart_response = \
					proxy['bosh_wait_for_restart_response']
			else:
				# http proxy
				proxy_dict['type'] = proxy['type']
				proxy_dict['xmpp_server'] = (self.xmpp_hostname, self.Port)
				proxy_dict['credentials'] = (proxy_user, proxy_pass)

		if not proxy or proxy['type'] != 'bosh':
			# Setup ordinary TCP transport
			self.socket = transports_nb.NonBlockingTCP.get_instance(
				on_disconnect=self.disconnect,
				raise_event=self.raise_event,
				idlequeue=self.idlequeue,
				estabilish_tls=establish_tls,
				certs=certs,
				proxy_dict=proxy_dict)

		# plug transport into client as self.Connection
		self.socket.PlugIn(self)

		self._resolve_hostname(
			hostname=tcp_host,
			port=tcp_port,
			on_success=self._try_next_ip)

	def _resolve_hostname(self, hostname, port, on_success):
		''' wrapper for getaddinfo call. FIXME: getaddinfo blocks'''
		try:
			self.ip_addresses = socket.getaddrinfo(hostname, port,
				socket.AF_UNSPEC, socket.SOCK_STREAM)
		except socket.gaierror, (errnum, errstr):
			self.disconnect(message='Lookup failure for %s:%s, hostname: %s - %s' %
				 (self.Server, self.Port, hostname, errstr))
		else:
			on_success()

	def _try_next_ip(self, err_message=None):
		'''Iterates over IP addresses tries to connect to it'''
		if err_message:
			log.debug('While looping over DNS A records: %s' % err_message)
		if self.ip_addresses == []:
			msg = 'Run out of hosts for name %s:%s.' % (self.Server, self.Port) 
			msg = msg + ' Error for last IP: %s' % err_message 
			self.disconnect(msg)
		else:
			self.current_ip = self.ip_addresses.pop(0)
			self.socket.connect(
				conn_5tuple=self.current_ip,
				on_connect=lambda: self._xmpp_connect(),
				on_connect_failure=self._try_next_ip)

	def incoming_stream_version(self):
		''' gets version of xml stream'''
		if 'version' in self.Dispatcher.Stream._document_attrs:
			return self.Dispatcher.Stream._document_attrs['version']
		else:
			return None

	def _xmpp_connect(self, socket_type=None):
		'''
		Starts XMPP connecting process - opens the XML stream. Is called after TCP
		connection is established or after switch to TLS when successfully
		negotiated with <starttls>.
		'''
		# socket_type contains info which transport connection was established
		if not socket_type:
			if self.Connection.ssl_lib:
				# When ssl_lib is set we connected via SSL
				socket_type = 'ssl'
			else:
				# PLAIN is default
				socket_type = 'plain'
		self.connected = socket_type
		self._xmpp_connect_machine()

	def _xmpp_connect_machine(self, mode=None, data=None):
		'''
		Finite automaton taking care of stream opening and features tag
		handling. Calls _on_stream_start when stream is started, and disconnect()
		on failure.
		'''
		log.info('-------------xmpp_connect_machine() >> mode: %s, data: %s...' %
			(mode, str(data)[:20]))

		def on_next_receive(mode):
			'''
			Sets desired on_receive callback on transport based on the state of
			connect_machine.
			'''
			log.info('setting %s on next receive' % mode)
			if mode is None:
				self.onreceive(None) # switch to Dispatcher.ProcessNonBlocking
			else:
				self.onreceive(lambda _data:self._xmpp_connect_machine(mode, _data))

		if not mode:
			# starting state
			if self.__dict__.has_key('Dispatcher'):
				self.Dispatcher.PlugOut()
				self.got_features = False
			dispatcher_nb.Dispatcher.get_instance().PlugIn(self)
			on_next_receive('RECEIVE_DOCUMENT_ATTRIBUTES')

		elif mode == 'FAILURE':
			self.disconnect('During XMPP connect: %s' % data)

		elif mode == 'RECEIVE_DOCUMENT_ATTRIBUTES':
			if data:
				self.Dispatcher.ProcessNonBlocking(data)
			if not hasattr(self, 'Dispatcher') or \
				self.Dispatcher.Stream._document_attrs is None:
				self._xmpp_connect_machine(
					mode='FAILURE',
					data='Error on stream open')
				return

			# if terminating stanza was received after init request then client gets
			# disconnected from bosh transport plugin and we have to end the stream
			# negotiating process straight away.
			# fixes #4657
			if not self.connected: return

			if self.incoming_stream_version() == '1.0':
				if not self.got_features:
					on_next_receive('RECEIVE_STREAM_FEATURES')
				else:
					log.info('got STREAM FEATURES in first recv')
					self._xmpp_connect_machine(mode='STREAM_STARTED')
			else:
				log.info('incoming stream version less than 1.0')
				self._xmpp_connect_machine(mode='STREAM_STARTED')

		elif mode == 'RECEIVE_STREAM_FEATURES':
			if data:
				# sometimes <features> are received together with document
				# attributes and sometimes on next receive...
				self.Dispatcher.ProcessNonBlocking(data)
			if not self.got_features:
				self._xmpp_connect_machine(
					mode='FAILURE',
					data='Missing <features> in 1.0 stream')
			else:
				log.info('got STREAM FEATURES in second recv')
				self._xmpp_connect_machine(mode='STREAM_STARTED')

		elif mode == 'STREAM_STARTED':
			self._on_stream_start()

	def _on_stream_start(self):
		'''
		Called after XMPP stream is opened.	TLS negotiation may follow if
		supported and desired.
		'''
		self.stream_started = True
		self.onreceive(None)

		if self.connected == 'plain':
			if self.desired_security == 'plain':
				# if we want and have plain connection, we're done now
				self._on_connect()
			else:
				# try to negotiate TLS
				if self.incoming_stream_version() != '1.0':
					# if stream version is less than 1.0, we can't do more
					log.warn('While connecting with type = "tls": stream version ' +
						'is less than 1.0')
					self._on_connect()
					return
				if self.Dispatcher.Stream.features.getTag('starttls'):
					# Server advertises TLS support, start negotiation
					self.stream_started = False
					log.info('TLS supported by remote server. Requesting TLS start.')
					self._tls_negotiation_handler()
				else:
					log.warn('While connecting with type = "tls": TLS unsupported ' +
						'by remote server')
					self._on_connect()
	
		elif self.connected in ['ssl', 'tls']:
			self._on_connect()
		else:
			assert False, 'Stream opened for unsupported connection'

	def _tls_negotiation_handler(self, con=None, tag=None):
		''' takes care of TLS negotioation with <starttls> '''
		log.info('-------------tls_negotiaton_handler() >> tag: %s' % tag)
		if not con and not tag:
			# starting state when we send the <starttls>
			self.RegisterHandlerOnce('proceed', self._tls_negotiation_handler,
					xmlns=NS_TLS)
			self.RegisterHandlerOnce('failure', self._tls_negotiation_handler,
					xmlns=NS_TLS)
			self.send('<starttls xmlns="%s"/>' % NS_TLS)
		else:
			# we got <proceed> or <failure>
			if tag.getNamespace() != NS_TLS:
				self.disconnect('Unknown namespace: %s' % tag.getNamespace())
				return
			tagname = tag.getName()
			if tagname == 'failure':
				self.disconnect('TLS <failure> received: %s' % tag)
				return
			log.info('Got starttls proceed response. Switching to TLS/SSL...')
			# following call wouldn't work for BOSH transport but it doesn't matter
			# because <starttls> negotiation with BOSH is forbidden
			self.Connection.tls_init(
				on_succ = lambda: self._xmpp_connect(socket_type='tls'),
				on_fail = lambda: self.disconnect('error while etabilishing TLS'))

	def _on_connect(self):
		''' preceeds call of on_connect callback '''
		self.onreceive(None)
		self.on_connect(self, self.connected)

	def raise_event(self, event_type, data):
		'''
		Raises event to connection instance. DATA_SENT and DATA_RECIVED events
		are used in XML console to show XMPP traffic
		'''
		log.info('raising event from transport: :::::%s::::\n_____________\n%s\n_____________\n' % (event_type,data))
		if hasattr(self, 'Dispatcher'):
			self.Dispatcher.Event('', event_type, data)

###############################################################################
### follows code for authentication, resource bind, session and roster download
###############################################################################

	def auth(self, user, password, resource='', sasl=True, on_auth=None):
		'''
		Authenticate connnection and bind resource. If resource is not provided
		random one or library name used.

		:param user: XMPP username
		:param password: XMPP password
		:param resource: resource that shall be used for auth/connecting
		:param sasl: Boolean indicating if SASL shall be used. (default: True)
		:param on_auth: Callback, called after auth. On auth failure, argument
			is None. 
		'''
		self._User, self._Password = user, password
		self._Resource, self._sasl = resource, sasl
		self.on_auth = on_auth
		self._on_doc_attrs()
		return
	
	def _on_old_auth(self, res):
		''' Callback used by NON-SASL auth. On auth failure, res is None. '''
		if res:
			self.connected += '+old_auth'
			self.on_auth(self, 'old_auth')
		else:
			self.on_auth(self, None)

	def _on_sasl_auth(self, res):
		''' Used internally. On auth failure, res is None. '''
		self.onreceive(None)
		if res:
			self.connected += '+sasl'
			self.on_auth(self, 'sasl')
		else:
			self.on_auth(self, None)

	def _on_doc_attrs(self):
		''' Plug authentication objects and start auth. '''
		if self._sasl:
			auth_nb.SASL.get_instance(self._User, self._Password,
				self._on_start_sasl).PlugIn(self)
		if not self._sasl or self.SASL.startsasl == 'not-supported':
			if not self._Resource:
				self._Resource = 'xmpppy'
			auth_nb.NonBlockingNonSASL.get_instance(self._User, self._Password,
				self._Resource, self._on_old_auth).PlugIn(self)
			return
		self.SASL.auth()
		return True
		
	def _on_start_sasl(self, data=None):
		''' Callback used by SASL, called on each auth step.'''
		if data:
			self.Dispatcher.ProcessNonBlocking(data)
		if not 'SASL' in self.__dict__:
			# SASL is pluged out, possible disconnect
			return
		if self.SASL.startsasl == 'in-process':
			return
		self.onreceive(None)
		if self.SASL.startsasl == 'failure':
			# wrong user/pass, stop auth
			if 'SASL' in self.__dict__:
				self.SASL.PlugOut()
			self.connected = None # FIXME: is this intended? We use ''elsewhere
			self._on_sasl_auth(None)
		elif self.SASL.startsasl == 'success':
			auth_nb.NonBlockingBind.get_instance().PlugIn(self)
			self.onreceive(self._on_auth_bind)
		return True
		
	def _on_auth_bind(self, data):
		# FIXME: Why use this callback and not bind directly?
		if data:
			self.Dispatcher.ProcessNonBlocking(data)
		if self.NonBlockingBind.bound is None:
			return
		self.NonBlockingBind.NonBlockingBind(self._Resource, self._on_sasl_auth)
		return True

	def initRoster(self):
		''' Plug in the roster. '''
		if not self.__dict__.has_key('NonBlockingRoster'):
			roster_nb.NonBlockingRoster.get_instance().PlugIn(self)

	def getRoster(self, on_ready=None):
		''' Return the Roster instance, previously plugging it in and
			requesting roster from server if needed. '''
		if self.__dict__.has_key('NonBlockingRoster'):
			return self.NonBlockingRoster.getRoster(on_ready)
		return None

	def sendPresence(self, jid=None, typ=None, requestRoster=0):
		''' Send some specific presence state.
			Can also request roster from server if according agrument is set.'''
		if requestRoster:
			# FIXME: used somewhere?
			roster_nb.NonBlockingRoster.get_instance().PlugIn(self)
		self.send(dispatcher_nb.Presence(to=jid, typ=typ))

###############################################################################
### following methods are moved from blocking client class of xmpppy
###############################################################################

	def RegisterDisconnectHandler(self,handler):
		''' Register handler that will be called on disconnect.'''
		self.disconnect_handlers.append(handler)

	def UnregisterDisconnectHandler(self,handler):
		''' Unregister handler that is called on disconnect.'''
		self.disconnect_handlers.remove(handler)

	def DisconnectHandler(self):
		'''
		Default disconnect handler. Just raises an IOError. If you choosed to use
		this class in your production client, override this method or at least
		unregister it.
		'''
		raise IOError('Disconnected from server.')

	def get_connect_type(self):
		''' Returns connection state. F.e.: None / 'tls' / 'plain+non_sasl'. '''
		return self.connected

	def get_peerhost(self):
		'''
		Gets the ip address of the account, from which is made connection to the
		server (e.g. IP and port of gajim's socket).
		We will create listening socket on the same ip
		'''
		# FIXME: tuple (ip, port) is expected (and checked for) but port num is
		# useless
		return self.socket.peerhost

# vim: se ts=3: